Technical Field
The disclosure relates to a microfluidic device, more particularly to a microfluidic device for generating monodisperse emulsions.
Background Information
Conventionally, for generating monodisperse emulsions, a microfluidic device as shown in FIG. 1 may be used. The microfluidic device includes a main channel 90 and two sub-channels 91, 92. An aqueous liquid 901 is delivered to the main channel 90, and an oily liquid 902 is delivered to the two sub-channels 91, 92. Both the aqueous liquid 901 and the oily liquid 902 are driven by a positive pressure supplied by syringe pumps (not shown). Droplets 903 are formed at a place where the aqueous liquid 901 and the oily liquid 902 meet, and are driven by the syringe pumps to an observation zone (not shown) of the microfluidic device for observation. For driving the aqueous liquid 901 and the oily liquid 902, the main channel 90 and the sub-channels 91, 92 are respectively connected to the syringe pumps by three narrow tubes (not shown). Therefore, it is relatively complicated to connect the microfluidic device with the syringe pumps.
In addition, if the aqueous liquid 901 and the oily liquid 902 are driven by a negative pressure applied at a location downstream of the main channel 90 and the sub-channels 91, 92, it is necessary to supply the amount of pressure needed to drive 901 and 902 simultaneously to thereby generate monodisperse emulsions. Besides, the microfluidic device using a negative pressure still needs to be connected to a syringe pump (not shown). Therefore, most researchers would prefer not to use a negative pressure to generate monodisperse emulsions.
One of the inventors of this application has proposed, in US patent application publication no. 2011/0247707 A1, a microfluidic chip device in which a fluid is driven by a negative pressure. However, the microfluidic chip device is not intended to generate monodisperse emulsions.